trench warfare on arms race map

[musicalmaven]

we are playing a trench warfare game on the arms race map.
how is the game won ?
if the rule on not being able to attack from a newly conquered territory applies, after conquering the warhead, if you cannot attack again, the warhead reverts back to a neutral and it keeps on repeating.

[Swifte]

Special Gameplay: Trench Warfare

With trench warfare you can only assault from regions held continuously since the start of your turn. If you conquer a region (or re-conquer a region) you cannot assault further from that region during the same turn. The one exception being 'killer neutrals' (explained on the Gameplay Notes page) from which you may continue assaulting. The game no longer involves steamrolling across the board. Instead you gradually advance your front!

[musicalmaven]

thanks